selftest: af_unix: Check EPOLLPRI after every send()/recv() in msg_oob.c

When OOB data is in recvq, we can detect it with epoll by checking
EPOLLPRI.

This patch add checks for EPOLLPRI after every send() and recv() in
all test cases.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

tools/testing/selftests/net/af_unix/msg_oob.c

@@ -6,6 +6,7 @@
 #include <unistd.h>
 
 #include <netinet/in.h>
+#include <sys/epoll.h>
 #include <sys/ioctl.h>
 #include <sys/signalfd.h>
 #include <sys/socket.h>
@@ -22,6 +23,9 @@ FIXTURE(msg_oob)
 				 * 3: TCP receiver
 				 */
 	int signal_fd;
+	int epoll_fd[2];	/* 0: AF_UNIX receiver
+				 * 1: TCP receiver
+				 */
 	bool tcp_compliant;
 };
 
@@ -109,6 +113,25 @@ static void setup_sigurg(struct __test_metadata *_metadata,
 	ASSERT_EQ(ret, -1);
 }
 
+static void setup_epollpri(struct __test_metadata *_metadata,
+			   FIXTURE_DATA(msg_oob) *self)
+{
+	struct epoll_event event = {
+		.events = EPOLLPRI,
+	};
+	int i;
+
+	for (i = 0; i < 2; i++) {
+		int ret;
+
+		self->epoll_fd[i] = epoll_create1(0);
+		ASSERT_GE(self->epoll_fd[i], 0);
+
+		ret = epoll_ctl(self->epoll_fd[i], EPOLL_CTL_ADD, self->fd[i * 2 + 1], &event);
+		ASSERT_EQ(ret, 0);
+	}
+}
+
 static void close_sockets(FIXTURE_DATA(msg_oob) *self)
 {
 	int i;
@@ -123,6 +146,7 @@ FIXTURE_SETUP(msg_oob)
 	create_tcp_socketpair(_metadata, self);
 
 	setup_sigurg(_metadata, self);
+	setup_epollpri(_metadata, self);
 
 	self->tcp_compliant = true;
 }
@@ -132,6 +156,29 @@ FIXTURE_TEARDOWN(msg_oob)
 	close_sockets(self);
 }
 
+static void __epollpair(struct __test_metadata *_metadata,
+			FIXTURE_DATA(msg_oob) *self,
+			bool oob_remaining)
+{
+	struct epoll_event event[2] = {};
+	int i, ret[2];
+
+	for (i = 0; i < 2; i++)
+		ret[i] = epoll_wait(self->epoll_fd[i], &event[i], 1, 0);
+
+	ASSERT_EQ(ret[0], oob_remaining);
+
+	if (self->tcp_compliant)
+		ASSERT_EQ(ret[0], ret[1]);
+
+	if (oob_remaining) {
+		ASSERT_EQ(event[0].events, EPOLLPRI);
+
+		if (self->tcp_compliant)
+			ASSERT_EQ(event[0].events, event[1].events);
+	}
+}
+
 static void __sendpair(struct __test_metadata *_metadata,
 		       FIXTURE_DATA(msg_oob) *self,
 		       const void *buf, size_t len, int flags)
@@ -254,6 +301,9 @@ static void __setinlinepair(struct __test_metadata *_metadata,
 			   expected_buf, expected_len, buf_len, flags);	\
 	} while (0)
 
+#define epollpair(oob_remaining)					\
+	__epollpair(_metadata, self, oob_remaining)
+
 #define setinlinepair()							\
 	__setinlinepair(_metadata, self)
 
@@ -265,109 +315,170 @@ static void __setinlinepair(struct __test_metadata *_metadata,
 TEST_F(msg_oob, non_oob)
 {
 	sendpair("x", 1, 0);
+	epollpair(false);
 
 	recvpair("", -EINVAL, 1, MSG_OOB);
+	epollpair(false);
 }
 
 TEST_F(msg_oob, oob)
 {
 	sendpair("x", 1, MSG_OOB);
+	epollpair(true);
 
 	recvpair("x", 1, 1, MSG_OOB);
+	epollpair(false);
 }
 
 TEST_F(msg_oob, oob_drop)
 {
 	sendpair("x", 1, MSG_OOB);
+	epollpair(true);
 
 	recvpair("", -EAGAIN, 1, 0);		/* Drop OOB. */
+	epollpair(false);
+
 	recvpair("", -EINVAL, 1, MSG_OOB);
+	epollpair(false);
 }
 
 TEST_F(msg_oob, oob_ahead)
 {
 	sendpair("hello", 5, MSG_OOB);
+	epollpair(true);
 
 	recvpair("o", 1, 1, MSG_OOB);
+	epollpair(false);
+
 	recvpair("hell", 4, 4, 0);
+	epollpair(false);
 }
 
 TEST_F(msg_oob, oob_break)
 {
 	sendpair("hello", 5, MSG_OOB);
+	epollpair(true);
 
 	recvpair("hell", 4, 5, 0);		/* Break at OOB even with enough buffer. */
+	epollpair(true);
+
 	recvpair("o", 1, 1, MSG_OOB);
+	epollpair(false);
 }
 
 TEST_F(msg_oob, oob_ahead_break)
 {
 	sendpair("hello", 5, MSG_OOB);
+	epollpair(true);
+
 	sendpair("world", 5, 0);
+	epollpair(true);
 
 	recvpair("o", 1, 1, MSG_OOB);
+	epollpair(false);
+
 	recvpair("hell", 4, 9, 0);		/* Break at OOB even after it's recv()ed. */
+	epollpair(false);
+
 	recvpair("world", 5, 5, 0);
+	epollpair(false);
 }
 
 TEST_F(msg_oob, oob_break_drop)
 {
 	sendpair("hello", 5, MSG_OOB);
+	epollpair(true);
+
 	sendpair("world", 5, 0);
+	epollpair(true);
 
 	recvpair("hell", 4, 10, 0);		/* Break at OOB even with enough buffer. */
+	epollpair(true);
+
 	recvpair("world", 5, 10, 0);		/* Drop OOB and recv() the next skb. */
+	epollpair(false);
+
 	recvpair("", -EINVAL, 1, MSG_OOB);
+	epollpair(false);
 }
 
 TEST_F(msg_oob, ex_oob_break)
 {
 	sendpair("hello", 5, MSG_OOB);
+	epollpair(true);
+
 	sendpair("wor", 3, MSG_OOB);
+	epollpair(true);
+
 	sendpair("ld", 2, 0);
+	epollpair(true);
 
 	recvpair("hellowo", 7, 10, 0);		/* Break at OOB but not at ex-OOB. */
+	epollpair(true);
+
 	recvpair("r", 1, 1, MSG_OOB);
+	epollpair(false);
+
 	recvpair("ld", 2, 2, 0);
+	epollpair(false);
 }
 
 TEST_F(msg_oob, ex_oob_drop)
 {
 	sendpair("x", 1, MSG_OOB);
+	epollpair(true);
+
 	sendpair("y", 1, MSG_OOB);		/* TCP drops "x" at this moment. */
+	epollpair(true);
 
 	tcp_incompliant {
 		recvpair("x", 1, 1, 0);		/* TCP drops "y" by passing through it. */
+		epollpair(true);
+
 		recvpair("y", 1, 1, MSG_OOB);	/* TCP returns -EINVAL. */
+		epollpair(false);
 	}
 }
 
 TEST_F(msg_oob, ex_oob_drop_2)
 {
 	sendpair("x", 1, MSG_OOB);
+	epollpair(true);
+
 	sendpair("y", 1, MSG_OOB);		/* TCP drops "x" at this moment. */
+	epollpair(true);
 
 	recvpair("y", 1, 1, MSG_OOB);
+	epollpair(false);
 
 	tcp_incompliant {
 		recvpair("x", 1, 1, 0);		/* TCP returns -EAGAIN. */
+		epollpair(false);
 	}
 }
 
 TEST_F(msg_oob, ex_oob_ahead_break)
 {
 	sendpair("hello", 5, MSG_OOB);
+	epollpair(true);
+
 	sendpair("wor", 3, MSG_OOB);
+	epollpair(true);
 
 	recvpair("r", 1, 1, MSG_OOB);
+	epollpair(false);
 
 	sendpair("ld", 2, MSG_OOB);
+	epollpair(true);
 
 	tcp_incompliant {
 		recvpair("hellowol", 8, 10, 0);	/* TCP recv()s "helloworl", why "r" ?? */
 	}
 
+	epollpair(true);
+
 	recvpair("d", 1, 1, MSG_OOB);
+	epollpair(false);
 }
 
 TEST_F(msg_oob, inline_oob)
@@ -375,9 +486,13 @@ TEST_F(msg_oob, inline_oob)
 	setinlinepair();
 
 	sendpair("x", 1, MSG_OOB);
+	epollpair(true);
 
 	recvpair("", -EINVAL, 1, MSG_OOB);
+	epollpair(true);
+
 	recvpair("x", 1, 1, 0);
+	epollpair(false);
 }
 
 TEST_F(msg_oob, inline_oob_break)
@@ -385,62 +500,94 @@ TEST_F(msg_oob, inline_oob_break)
 	setinlinepair();
 
 	sendpair("hello", 5, MSG_OOB);
+	epollpair(true);
 
 	recvpair("", -EINVAL, 1, MSG_OOB);
+	epollpair(true);
+
 	recvpair("hell", 4, 5, 0);		/* Break at OOB but not at ex-OOB. */
+	epollpair(true);
+
 	recvpair("o", 1, 1, 0);
+	epollpair(false);
 }
 
 TEST_F(msg_oob, inline_oob_ahead_break)
 {
 	sendpair("hello", 5, MSG_OOB);
+	epollpair(true);
+
 	sendpair("world", 5, 0);
+	epollpair(true);
 
 	recvpair("o", 1, 1, MSG_OOB);
+	epollpair(false);
 
 	setinlinepair();
 
 	recvpair("hell", 4, 9, 0);		/* Break at OOB even with enough buffer. */
+	epollpair(false);
 
 	tcp_incompliant {
 		recvpair("world", 5, 6, 0);	/* TCP recv()s "oworld", ... "o" ??? */
 	}
+
+	epollpair(false);
 }
 
 TEST_F(msg_oob, inline_ex_oob_break)
 {
 	sendpair("hello", 5, MSG_OOB);
+	epollpair(true);
+
 	sendpair("wor", 3, MSG_OOB);
+	epollpair(true);
+
 	sendpair("ld", 2, 0);
+	epollpair(true);
 
 	setinlinepair();
 
 	recvpair("hellowo", 7, 10, 0);		/* Break at OOB but not at ex-OOB. */
+	epollpair(true);
+
 	recvpair("rld", 3, 3, 0);
+	epollpair(false);
 }
 
 TEST_F(msg_oob, inline_ex_oob_no_drop)
 {
 	sendpair("x", 1, MSG_OOB);
+	epollpair(true);
 
 	setinlinepair();
 
 	sendpair("y", 1, MSG_OOB);		/* TCP does NOT drops "x" at this moment. */
+	epollpair(true);
 
 	recvpair("x", 1, 1, 0);
+	epollpair(true);
+
 	recvpair("y", 1, 1, 0);
+	epollpair(false);
 }
 
 TEST_F(msg_oob, inline_ex_oob_drop)
 {
 	sendpair("x", 1, MSG_OOB);
+	epollpair(true);
+
 	sendpair("y", 1, MSG_OOB);		/* TCP drops "x" at this moment. */
+	epollpair(true);
 
 	setinlinepair();
 
 	tcp_incompliant {
 		recvpair("x", 1, 1, 0);		/* TCP recv()s "y". */
+		epollpair(true);
+
 		recvpair("y", 1, 1, 0);		/* TCP returns -EAGAIN. */
+		epollpair(false);
 	}
 }